The commonly seen optical disk drives at present can be categorized as tray loading type and leaf-actuation loading type. The former type is usually used on desktop computers, while the later type is mostly adopted on notebook computers. The tray loading type requires greater space. When in use, the tray has to be ejected for loading the optical disc, and the tray is withdrawn into the optical disk drive for reading. Ejection of the tray requires a lot of space. Moreover, impact may occur and damage the disk drive. If the optical disc is not properly positioned when the tray is withdrawn, the optical disc will be jammed between the tray and the optical disk drive.
The leaf-actuation loading type is generally used when space is constrained. It is mostly used in notebook computers. However, during ejection the optical module and the tray are ejected together. If a slight error happens while placing or removing the optical disc, the optical module is easily scraped and damaged, and could result in dysfunction of the optical disk drive.
In order to overcome the aforesaid disadvantages, U.S. Pat. No. 6,414,927 discloses a roller loading method. Its main design concept is to deploy an elongated roller on the exit of the optical disc drive. When an optical disc is inserted, the roller conveys the optical disc to a correct position by friction. As it is driven by roller friction, it can be adapted to optical discs of various sizes (commonly 8 cm and 12 cm). However, because it is driven by roller friction, the surface of the disc is frequently scraped and damaged during the conveying process. Moreover, if the roller is smeared by dust or external objects, it could cut into the disc surface and cause serious damage.
U.S. Pat. No. 6,449,234 discloses another type of loading scheme that uses an actuating lever to move the optical disc. While it can save the tray and avoid the problem of scraping the disc surface occurring with U.S. Pat. No. 6,414,927, it cannot be adapted for different sizes of discs.